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Technical Committee
Private Network-Network Interface
Specification Version 1.0
(PNNI 1.0)
af-pnni-0055.000
March 1996
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(c) 1996 The ATM Forum. All Rights Reserved. No part of this publication may be reproduced in any
form or by any means.
The information in this publication is believed to be accurate as of its publication date. Such information
is subject to change without notice and the ATM Forum is not responsible for any errors. The ATM
Forum does not assume any responsibility to update or correct any information in this publication.
Notwithstanding anything to the contrary, neither the ATM Forum nor the publisher make anyrepresentation or warranty, expressed or implied, concerning the completeness, accuracy, or applicability
of any information contained in this publication. No liability of any kind shall be assumed by The ATM
Forum or the publisher as a result of reliance upon any information contained in this publication.
The receipt or any use of this document or its contents does not in any way create by implication or
otherwise:
Any express or implied license or right to or under any ATM Forum member companys patent,
copyright, trademark, or trade secret rights which are or may be associated with the ideas,
techniques, concepts or expressions contained herein; nor
Any warranty or representation that any ATM Forum member companies will announce any
product(s) and/or service(s) related thereto, or if such announcements are made, that such announced
product(s) and/or service(s) embody any or all of the ideas, technologies, or concepts contained
herein; nor Any form of relationship between any ATM Forum member companies and the recipient or user of
this document.
Implementation or use of specific ATM standards or recommendations and ATM Forum specifications
will be voluntary, and no company shall agree or be obliged to implement them by virtue of participation
in the ATM Forum. The ATM Forum is a non-profit international organization accelerating industry
cooperation on ATM technology. The ATM Forum does not, expressly or otherwise, endorse or promote
any specific products or services.
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Acknowledgements
The PNNI SWG was chaired by Mike Goguen. Doug Dykeman was the editor for the PNNI Routing
related sections of the document, and Rao Cherukuri for PNNI Signalling. The official meeting minutes
were taken by Jason Jeffords.
The following people made significant technical contributions to the PNNI specification:
Masuma Ahmed Juha Heinanen Russell Pretty
Anthony Alles Tom Helstern Tony Przygienda
Francois Audet Michael Hluchyj John Rutemiller
Tomas Berggren Eric Hoffman Abdallah Saleh
Caralyn Brown Heinrich Hummel Bill Salkewicz
David Bucciero Nick Huslak Hal Sandick
Ross Callon Jason Jeffords Shirish Sathaye
Rao Cherukuri Martin Johnsson Ross Schibler
Ashok Chippa Claude Kawa Jean-Bernard Schmitt
Rob Coltun John Keene Stephen Shew
David Cypher Walter Knitl F. Y. Simon
Roger Dev Paul Koning Kumar Sivarajan
R. Dianda Garry Kump Ethan Spiegel
John Drake Whay Lee Ed Sullivan
Tim Dwight Fong-Ching Liaw Hiroshi Suzuki
Doug Dykeman Sandrine Masson George Swallow
John Elwell Keith McCloghrie Ted Tedijanto
Robert Epley Dave McDysan Kamlesh Tewani
Norman Finn John Moy Marek Tomaszewski
Mike Goguen Raj Nair Joachim Wagner
Dan Grossman Maryann Perez James Watt
Joel Halpern Drew Perkins David Wells
S. Kamran Hasan Bernhard Petri Malcolm WilesTim Hefel Paul Phillips
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Table of Contents
1. INTRODUCTION...............................................................................................................................1
1.1 OVERVIEW .......................................................................................................................................1
1.2 REFERENCE MODELS ........................................................................................................................11.3 PNNI STATUS ..................................................................................................................................2
1.4 DOCUMENT ORGANIZATION ..............................................................................................................2
1.5 REFERENCES ....................................................................................................................................2
2. TERMINOLOGY ............... ............... .................. ............... .................. .................. ............... .............4
2.1 ABBREVIATIONS ...............................................................................................................................4
2.2 DEFINITIONS ....................................................................................................................................5
2.3 NOTATION AND CONVENTIONS........................................................................................................12
3. PNNI ROUTING DESCRIPTION....................................................................................................13
3.1 PHYSICAL NETWORK ......................................................................................................................13
3.2 THE LOWEST HIERARCHICAL LEVEL ................................................................................................14
3.2.1 Peer Groups and Logical Nodes .............................................................................................143.2.2 Logical Links And Their Initialization.....................................................................................15
3.2.3 Information Exchange in PNNI...............................................................................................15
3.2.3.1 Nodal Information ...........................................................................................................................16
3.2.3.2 Topology State Information .............................................................................................................16
3.2.3.3 Reachability Information.................................................................................................................16
3.2.3.4 Initial Topology Database Exchange ...............................................................................................16
3.2.3.5 Flooding..........................................................................................................................................17
3.2.4 Peer Group Leader ................... ...................... ................... ..................... ............... .......... .......17
3.3 ONE HIERARCHICAL LEVEL UP ........................................................................................................18
3.3.1 Logical Group Nodes..............................................................................................................18
3.3.2 Feeding Information Up The Hierarchy ........................................ ........................ ........... .......20
3.3.3 Feeding Information Down The Hierarchy..............................................................................20
3.3.4 Uplinks (Revisiting The Hello Protocol)..................................................................................203.3.5 PNNI Routing Control Channels.............................................................................................22
3.3.6 Revisiting Initial Topology Database Exchange......................................................................23
3.3.7 Horizontal Links .................. ...................... ................... ..................... .................... ... .......... ....23
3.3.8 Topology Aggregation ............................................................................................................24
3.3.8.1 Link Aggregation.............................................................................................................................24
3.3.8.2 Nodal Aggregation ..........................................................................................................................24
3.4 COMPLETING THE PNNI ROUTING HIERARCHY ...............................................................................26
3.4.1 Progressing To The Highest Level Peer Group .......................................................................27
3.4.2 Uplinks And Horizontal links Revisited...................................................................................27
3.4.3 Recursion in the Hierarchy.....................................................................................................28
3.5 ADDRESS SUMMARIZATION & REACHABILITY..................................................................................29
3.5.1 Address Scoping .....................................................................................................................32
3.5.1.1 An Example of Address Summarization with Address Scoping..........................................................323.6 SINGLE NODE PERSPECTIVE ............................................................................................................35
3.7 PATH SELECTION ............................................................................................................................36
3.7.1 Generic Connection Admission Control ....................... ............................ ............................ ...38
4. PNNI SIGNALLING DESCRIPTION..............................................................................................39
4.1 INTRODUCTION...............................................................................................................................39
4.2 OVERVIEW .....................................................................................................................................39
4.3 ASSOCIATED SIGNALLING ...............................................................................................................40
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4.4 DESIGNATED TRANSIT LISTS ...........................................................................................................40
4.5 CRANKBACK...................................................................................................................................40
4.6 SOFT PVPCS AND PVCCS...............................................................................................................40
4.7 AN EXAMPLE OF CONNECTION SETUP WITH CRANKBACK .................................................................41
4.8 SUPPORTING ANYCAST WITH SCOPING.............................................................................................45
5. PNNI ROUTING SPECIFICATION................................................................................................47
5.1 GENERAL OPERATIONAL PROCEDURES ............................................................................................47
5.1.1 Timers ....................................................................................................................................47
5.1.2 Packet Transmission ............. ............. ............... ............. ............... ............. ............. ............... .47
5.1.3 Packet Validation ...................................................................................................................47
5.2 ADDRESSING ..................................................................................................................................48
5.2.1 ATM Addressing Convention ..................................................................................................48
5.2.2 Node Addresses ......................................................................................................................49
5.2.3 End System Addresses.............................................................................................................49
5.3 IDENTIFIERS AND INDICATORS.........................................................................................................49
5.3.1 Level Indicators......................................................................................................................49
5.3.2 Peer Group Identifiers .................... ..................... ................... ...................... ..................... .....50
5.3.3 Node Identifiers .............. ................ ................. ................ ................. .................. ............... .....50
5.3.4 Port Identifiers and Logical Links...........................................................................................515.3.5 Aggregation Tokens ................ ............... .................. .................. ............... .................. ............51
5.3.6 Scope of Addresses .................................................................................................................52
5.4 LOGICAL LINKS ..............................................................................................................................52
5.5 PNNI ROUTING CONTROL CHANNELS .............................................................................................52
5.5.1 Specification of the AAL used by the PNNI Routing Control Channel ................................ .....53
5.5.2 Traffic Contract for RCCs over Physical Links ........................................ ........................ .......53
5.5.3 Traffic Contract for RCCs over VPCs ....................................... ............................... . .......... ....53
5.5.4 SVCC-Based RCC Connection Establishment Overview..........................................................545.5.4.1 SETUP Message Contents ...............................................................................................................54
5.5.4.1.1 AAL Parameters.......................................................................................................................54
5.5.4.1.2 ATM Traffic Descriptor............................................................................................................55
5.5.4.1.3 Broadband Bearer Capability....................................................................................................55
5.5.4.1.4 Broadband Low Layer Information............................................................................................565.5.4.1.5 QoS Parameter .........................................................................................................................56
5.5.4.1.6 Extended QoS Parameters ........................................................................................................56
5.5.4.1.7 End-to-End Transit Delay.........................................................................................................57
5.5.4.1.8 Called Party Number................................................................................................................57
5.5.4.1.9 Calling Party Number...............................................................................................................57
5.5.4.1.10 Connection Identifier ..............................................................................................................57
5.5.4.1.11 DTL .......................................................................................................................................57
5.5.4.2 CONNECT Message Contents.........................................................................................................57
5.5.4.2.1 AAL Parameters.......................................................................................................................58
5.5.4.2.2 Broadband Low Layer Information............................................................................................58
5.5.4.2.3 Connection Identifier................................................................................................................58
5.5.4.3 RELEASE and RELEASE COMPLETE Message Contents..............................................................58
5.5.5 SVCCs when One End is not an LGN ............ ............. ............... ............. ............... ............. .....58
5.5.6 Establishing and Maintaining SVCCs between Logical Group Nodes......................................595.5.6.1 SVCC Establishment.......................................................................................................................59
5.5.6.2 Inconsistent Information and Partitioned Neighbor Peer Groups.......................................................60
5.5.6.3 Detailed Mechanisms for Establishment and Maintenance of SVCCs...............................................60
5.6 THE HELLO PROTOCOL ...................................................................................................................62
5.6.1 PNNI Version Negotiation ......................................................................................................62
5.6.2 Hellos Over Physical Links and VPCs.....................................................................................625.6.2.1 The Hello State Machine .................................................................................................................62
5.6.2.1.1 The Hello Data Structure..........................................................................................................63
5.6.2.1.2 Hello States..............................................................................................................................65
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5.6.2.1.3 Events causing Hello state changes...........................................................................................66
5.6.2.1.4 Description of The Hello State Machine ...................................................................................68
5.6.2.2 Sending Hellos ................................................................................................................................73
5.6.2.2.1 Originating and sending ULIAs in Hellos on Outside Links ....... ........ ........ ........ .......... ........ .....74
5.6.2.3 Receiving Hellos .............................................................................................................................74
5.6.2.3.1 Processing ULIAs received in Hellos on outside links...............................................................75
5.6.3 The LGN Hello Protocol.........................................................................................................75
5.6.3.1 SVCC-Based RCC Hello Protocol....................................................................................................765.6.3.1.1 The SVCC-Based RCC Hello Data Structure ............................................................................77
5.6.3.1.2 SVCIntegrityTimer...................................................................................................................77
5.6.3.1.3 Loss of Neighbor Relationship..................................................................................................78
5.6.3.2 LGN Horizontal Link Hello Protocol................................................................................................78
5.6.3.2.1 The LGN Horizontal Link Hello Data Structure ........ ........ ........ ......... ........ ........ ........ .......... .....79
5.6.3.2.2 LGN Horizontal Link States .....................................................................................................79
5.6.3.2.3 LGN Horizontal Link Events ....................................................................................................80
5.6.3.2.4 Description of The Horizontal Link Hello State Machine ........ ........ ........ .......... ........ ........ ........ 82
5.6.3.3 Overall Procedures ..........................................................................................................................84
5.7 DATABASE SYNCHRONIZATION .......................................................................................................85
5.7.1 The Neighboring Peer Data Structure.....................................................................................86
5.7.2 Neighboring Peer States ................. ..................... ................... ...................... ..................... .....88
5.7.3 Events causing neighboring peer state changes ......................................................................89
5.7.4 The Neighboring Peer State Machine......................................................................................90
5.7.5 Sending Database Summary Packets.......................................................................................92
5.7.6 Receiving Database Summary Packets....................................................................................93
5.7.7 Sending PTSE Request Packets...............................................................................................95
5.7.8 Receiving PTSE Request Packets ................... ..................... .................... ..................... ...........96
5.8 TOPOLOGY DESCRIPTION AND DISTRIBUTION...................................................................................96
5.8.1 Topology Information ................. ..................... ................... ...................... ..................... .........965.8.1.1 Topology State Parameters...............................................................................................................96
5.8.1.1.1 Link State Parameters...............................................................................................................97
5.8.1.1.2 Nodal State Parameters ............................................................................................................97
5.8.1.1.3 Resource Availability Information Group (RAIG) ........ ........ ........ ......... ........ ........ ........ .......... ..97
5.8.1.1.3.1 Resource Availability Information Group Flags..................................................................98
5.8.1.1.3.2 Cell Delay Variation (CDV) ..............................................................................................98
5.8.1.1.3.3 Maximum Cell Transfer Delay (maxCTD).........................................................................985.8.1.1.3.4 Administrative Weight (AW).............................................................................................98
5.8.1.1.3.5 Cell Loss Ratio for CLP=0 (CLR0).....................................................................................99
5.8.1.1.3.6 Cell Loss Ratio for CLP=0+1 (CLR0+1) ..............................................................................99
5.8.1.1.3.7 Maximum Cell Rate (maxCR)...........................................................................................99
5.8.1.1.3.8 Available Cell Rate (AvCR)..............................................................................................99
5.8.1.1.3.9 Cell Rate Margin (CRM).................................................................................................100
5.8.1.1.3.10 Variance Factor (VF).....................................................................................................100
5.8.1.2 Nodal Information .........................................................................................................................100
5.8.1.2.1 ATM End System Address of the Node...................................................................................100
5.8.1.2.2 Leadership Priority .................................................................................................................100
5.8.1.2.3 Nodal Information Flags.........................................................................................................100
5.8.1.2.4 Preferred Peer Group Leader Node ID ....................................................................................101
5.8.1.2.5 Next Higher Level Binding Information..................................................................................102
5.8.1.2.5.1 Parent Logical Group Node ID.........................................................................................1025.8.1.2.5.2 Parent Logical Group Nodes ATM End System Address... ........ ........ ........ .......... ........ ....102
5.8.1.2.5.3 Parent Peer Group ID ......................................................................................................102
5.8.1.2.5.4 Node ID of PGL of Parent Peer Group .............................................................................102
5.8.1.3 Reachability Information................................................................................................................102
5.8.1.3.1 Internal Reachable Addresses .................................................................................................102
5.8.1.3.2 Exterior Reachable ATM Addresses .......................................................................................103
5.8.2 PTSPs and PTSEs ............. ............. ............... ............. .............. ............. ............. ............... ....1045.8.2.1 PTSPs ...........................................................................................................................................104
5.8.2.2 PTSEs ...........................................................................................................................................105
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5.8.2.2.1 PTSE Header Contents ...........................................................................................................105
5.8.2.2.2 PTSE Checksum algorithm.....................................................................................................106
5.8.2.2.3 PTSE identification and PTSE instance identification ........ ........ ........ ......... ........ ........ ........ ....106
5.8.2.2.4 Comparison of PTSE instances ...............................................................................................106
5.8.3 Flooding...............................................................................................................................1075.8.3.1 Overview.......................................................................................................................................107
5.8.3.2 Sending PTSPs..............................................................................................................................107
5.8.3.3 Receiving a PTSP..........................................................................................................................1085.8.3.4 Processing of Peer Retransmission List..........................................................................................110
5.8.3.5 Sending of PTSE Acknowledgments ..............................................................................................110
5.8.3.6 Receiving Acknowledgment Packets ........ ........ ......... ......... ........ ........ ........ ......... ......... ........ ........ ..110
5.8.3.7 Origination of a New PTSE or a new PTSE Instance......................................................................110
5.8.3.8 Expiration of a PTSEs Lifetime ....................................................................................................111
5.8.3.9 Removal of PTSEs from the topology database...............................................................................111
5.8.4 Aging PTSEs in the Topology Database................................................................................1125.8.4.1 Computing the Remaining Lifetime of a PTSE...............................................................................112
5.8.4.2 Refreshing Self-originated PTSEs..................................................................................................112
5.8.5 Triggered Updates of Topology Information .................................... ............................ .........1125.8.5.1 Significant Change Events for PNNI Topology State Elements ....... ........ ......... ......... ........ ........ ...... 112
5.8.5.2 Processing Significant Changes to PTSEs ......................................................................................113
5.8.5.2.1 Changes in Nodal Information Groups ....................................................................................113
5.8.5.2.2 Changes in Internal Reachable ATM Addresses IGs................................................................1135.8.5.2.3 Changes in Exterior Reachable ATM Addresses IGs...............................................................113
5.8.5.2.4 Changes in other information groups.......................................................................................114
5.8.5.2.5 Changes to Resource Availability Information.........................................................................114
5.8.5.2.5.1 Administrative Weight ( AW ).........................................................................................114
5.8.5.2.5.2 Cell Loss Ratio ( CLR0 )..................................................................................................114
5.8.5.2.5.3 Cell Loss Ratio ( CLR0+1 ) ...............................................................................................114
5.8.5.2.5.4 Available Cell Rate ( AvCR ) ..........................................................................................114
5.8.5.2.5.5 Maximum Cell Transfer Delay ( maxCTD ).....................................................................115
5.8.5.2.5.6 Cell Delay Variation ( CDV ) ..........................................................................................116
5.8.5.2.5.7 Maximum Cell Rate ( maxCR ) .......................................................................................117
5.8.5.2.5.8 Cell Rate Margin ( CRM ) and Variance Factor ( VF ).....................................................117
5.9 ADVERTISING AND SUMMARIZING REACHABLE ADDRESSES............................................................117
5.9.1 Scope of Advertisement of Addresses ....................................................................................117
5.9.2 Summary Address and Suppressed Summary Address............................................................118
5.9.3 Native Addresses ..................................................................................................................118
5.9.4 Foreign Addresses ................................................................................................................118
5.9.5 Group Addresses...................................................................................................................119
5.9.6 Exterior Reachable Addresses ..............................................................................................119
5.10 HIERARCHY................................................................................................................................119
5.10.1 Peer Group Leader .............................................................................................................1195.10.1.1 Peer Group Leader Election Algorithm ........................................................................................119
5.10.1.1.1 The PGL Election Data Structure..........................................................................................119
5.10.1.1.2 PGL Election States..............................................................................................................120
5.10.1.1.3 Events Causing Neighboring Peer State Changes ........ ........ ........ .......... ........ ........ ........ ........ 123
5.10.1.1.4 The PGL Election State Machine ..........................................................................................124
5.10.1.1.5 Sending a Nodal Information PTSE.......................................................................................128
5.10.1.1.6 Choosing Preferred PGL.......................................................................................................1285.10.1.2 Leadership Priority ......................................................................................................................129
5.10.1.2.1 Group Leader Increment .......................................................................................................129
5.10.1.2.2 Distinguished Values and Range Restrictions .......................................................................129
5.10.1.2.3 Range Recommendations......................................................................................................129
5.10.1.2.4 Implications of Hierarchy......................................................................................................129
5.10.1.3 Default Configuration Consistency...............................................................................................130
5.10.1.4 Operation Without a Peer Group Leader ......................................................................................130
5.10.1.5 Exchange of Nodal Hierarchy Information on Outside Links.........................................................130
5.10.2 Advertising Uplinks ............................................................................................................131
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5.10.2.1 Advertising Uplinks from Lowest Level Nodes ........ ........ ........ ......... ........ ......... ........ ......... ........ .131
5.10.2.2 Reverse Direction Information in Uplinks ....................................................................................131
5.10.3 Topology Aggregation ........................................................................................................1325.10.3.1 Link Aggregation and Binding Information ........ ........ ........ .......... ........ ........ ........ ......... ........ ....... 132
5.10.3.2 Simple Node Representation........................................................................................................134
5.10.3.3 Complex Node Representation.....................................................................................................134
5.10.4 Feeding Information Down the Hierarchy...........................................................................136
5.10.5 Flushing PTSEs in a Multi-Level Hierarchy........................................................................138
5.11 PEER GROUP PARTITIONS ............................................................................................................138
5.11.1 Representation of the partition in the hierarchy..................................................................138
5.11.2 Routing in the Presence of Partitions..................................................................................139
5.11.3 What to Aggregate as Peer Group Leader...........................................................................139
5.12 OPERATION OF A NODE WHEN IN A TOPOLOGY DATABASE OVERLOAD STATE ................................140
5.12.1 Requirement for operation in topology database overload state..........................................1405.12.1.1 Minimum state required ..............................................................................................................140
5.12.1.2 Disallowed Functions ..................................................................................................................140
5.12.1.3 PGL election................................................................................................................................140
5.12.1.4 PTSP reception and transmission.................................................................................................140
5.12.1.5 Periodic resynchronization...........................................................................................................141
5.12.2 Recommendations for operation in topology database overload state .................................141
5.12.2.1 Call processing............................................................................................................................1415.12.2.2 Topology database handling.........................................................................................................142
5.13 PATH SELECTION ........................................................................................................................142
5.13.1 Eligible Entities for Path Selection ................. ..................... ................... ...................... ......143
5.13.2 Link Constraints, Node Constraints, and Path Constraints .................................... ........... ..143
5.13.3 CLR Selection for CBR andVBR Service .................. ...................... ................... ..................144
5.13.4 Generic CAC Algorithm for CBR and VBR Services ...........................................................1445.13.4.1 Parameter Choice for GCAC........................................................................................................144
5.13.4.2 Complex GCAC ..........................................................................................................................146
5.13.4.2.1 Algorithm.............................................................................................................................146
5.13.4.2.2 Special Cases .......................................................................................................................146
5.13.4.2.3 Optional Improvement to Algorithm......................................................................................146
5.13.4.3 Simple GCAC .............................................................................................................................146
5.13.5 Generic CAC Algorithm for Best-Effort Service..................................................................1475.13.5.1 Minimum Acceptable ATM Traffic Descriptor.............................................................................147
5.14 PACKET FORMATS ......................................................................................................................147
5.14.1 Notation..............................................................................................................................148
5.14.2 Information Group Tags......................................................................................................1485.14.2.1 Mandatory Tag ............................................................................................................................148
5.14.2.2 Summarizing Tag ........................................................................................................................149
5.14.2.3 Transitive Tag .............................................................................................................................149
5.14.2.4 Mandatory Non-Transitive Information Groups........ ........ ........ ......... ........ ......... ........ ......... ........ .149
5.14.2.5 Examples.....................................................................................................................................150
5.14.2.5.1 Advisory Metrics and Attributes ...........................................................................................150
5.14.2.5.2 Local Information Groups .....................................................................................................150
5.14.2.5.3 User lists..............................................................................................................................150
5.14.2.5.4 Security Labels.....................................................................................................................150
5.14.2.6 Information Group Tag Bit Definitions.........................................................................................1505.14.3 Information Group Summary...............................................................................................152
5.14.4 PNNI Packet Header...........................................................................................................154
5.14.5 The Resource Availability Information Group.....................................................................154
5.14.6 Uplink Information Attribute...............................................................................................155
5.14.7 Transit Network ID .............................................................................................................156
5.14.8 PNNI Hellos .......................................................................................................................1575.14.8.1 The Aggregation Token IG...........................................................................................................158
5.14.8.2 The Nodal Hierarchy List IG........................................................................................................158
5.14.8.3 The LGN Horizontal Link Extension IG.......................................................................................159
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5.14.9 PNNI Topology State Packets (PTSP) .................................................................................1595.14.9.1 Restricted Information Groups .....................................................................................................161
5.14.9.1.1 The Nodal state parameters IG..............................................................................................161
5.14.9.1.2 The Nodal Information Group...............................................................................................161
5.14.9.1.3 The Internal Reachable ATM Addresses Information Group..................................................163
5.14.9.1.4 The Exterior Reachable ATM addresses Information Group..................................................163
5.14.9.1.5 The Horizontal Links Information Group ........ ......... ........ ......... ........ ........ ........ .......... ........ ..164
5.14.9.1.6 The Uplinks Information Group............................................................................................1655.14.9.2 Unrestricted Information Groups..................................................................................................165
5.14.9.3 Unknown Information Groups......................................................................................................166
5.14.9.4 Processing PTSEs Violating Restrictions .....................................................................................166
5.14.9.5 PTSE Error Scenarios ..................................................................................................................166
5.14.9.5.1 Nodal Info Group in Nodal Info PTSE...................................................................................167
5.14.9.5.2 Next higher Level Binding TLV in Nodal Info TLV..............................................................167
5.14.9.5.3 Nodal State Parameters TLV ................................................................................................167
5.14.9.5.4 Horizontal Link TLV............................................................................................................168
5.14.9.5.5 Uplink TLV..........................................................................................................................168
5.14.9.5.6 ULIA....................................................................................................................................168
5.14.9.5.7 RAIGs..................................................................................................................................168
5.14.9.6 Nodal Info PTSE and its connection to other PTSEs issued by the node........................................168
5.14.10 PTSE Acknowledgment Packets.........................................................................................169
5.14.11 Database Summary Packets ......................... ............................ ............................ .............1695.14.12 PTSE Request Packets ......................................................................................................171
5.14.13 System Capabilities...........................................................................................................172
6. PNNI SIGNALLING SPECIFICATION........................................................................................173
6.1 PNNI MODEL ...............................................................................................................................173
6.1.1 Definitions............................................................................................................................173
6.1.2 Protocol model .....................................................................................................................1736.1.2.1 Signalling layer .............................................................................................................................174
6.1.2.2 Signalling adaptation layer ............................................................................................................174
6.1.2.3 ATM layer.....................................................................................................................................175
6.2 OVERVIEW OF CALL/CONNECTION CONTROL ..................................................................................175
6.2.1 ATM Point-to-point call states ................. ..................... ................... ...................... ...............175
6.2.1.1 Null (NN0)....................................................................................................................................1756.2.1.2 Call Initiated (NN1) ......................................................................................................................175
6.2.1.3 Call Proceeding Sent (NN3) ..........................................................................................................175
6.2.1.4 Alerting Delivered (NN4)..............................................................................................................175
6.2.1.5 Call Present (NN6)........................................................................................................................175
6.2.1.6 Alerting Received (NN7)...............................................................................................................176
6.2.1.7 Call Proceeding Received (NN9) ...................................................................................................176
6.2.1.8 Active (NN10)...............................................................................................................................176
6.2.1.9 Release Request (NN11) ...............................................................................................................176
6.2.1.10 Release Indication (NN12)...........................................................................................................176
6.2.2 States associated with global call reference..........................................................................176
6.3 MESSAGE FUNCTIONAL DEFINITIONS AND CONTENTS ......................................................................176
6.3.1 Messages for ATM point-to-point call and connection control ..............................................1776.3.1.1 ALERTING...................................................................................................................................177
6.3.1.2 CALL PROCEEDING ...................................................................................................................1786.3.1.3 CONNECT....................................................................................................................................178
6.3.1.4 RELEASE .....................................................................................................................................179
6.3.1.5 RELEASE COMPLETE ................................................................................................................180
6.3.1.6 SETUP..........................................................................................................................................180
6.3.1.7 STATUS .......................................................................................................................................182
6.3.1.8 STATUS ENQUIRY......................................................................................................................182
6.3.1.9 NOTIFY........................................................................................................................................183
6.3.2 Additional or modified messages for the support of 64kbit/s based ISDN circuit mode services1836.3.2.1 ALERTING...................................................................................................................................184
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6.3.2.2 CONNECT....................................................................................................................................184
6.3.2.3 PROGRESS ..................................................................................................................................185
6.3.2.4 RELEASE .....................................................................................................................................185
6.3.2.5 SETUP..........................................................................................................................................186
6.3.3 Messages used with the global call reference........................................................................1866.3.3.1 RESTART.....................................................................................................................................186
6.3.3.2 RESTART ACKNOWLEDGE.......................................................................................................187
6.3.4 Messages for Point-to-multipoint call and connection control...............................................1876.3.4.1 ADD PARTY ................................................................................................................................188
6.3.4.2 ADD PARTY ACKNOWLEDGE ..................................................................................................189
6.3.4.3 PARTY ALERTING......................................................................................................................189
6.3.4.4 ADD PARTY REJECT..................................................................................................................190
6.3.4.5 DROP PARTY..............................................................................................................................191
6.3.4.6 DROP PARTY ACKNOWLEDGE ................................................................................................191
6.4 GENERAL MESSAGE FORMAT AND INFORMATION ELEMENT CODING .................................................192
6.4.1 Overview ..............................................................................................................................192
6.4.2 Protocol discriminator..........................................................................................................192
6.4.3 Call reference.......................................................................................................................192
6.4.4 Message type and message length.........................................................................................1926.4.4.1 Message type.................................................................................................................................192
6.4.4.2 Message length..............................................................................................................................1936.4.5 Variable length information elements ...................................................................................193
6.4.5.1 Coding rules..................................................................................................................................193
6.4.5.2 Extension of codesets ....................................................................................................................194
6.4.5.3 Broadband locking shift procedures ...............................................................................................194
6.4.5.4 Broadband non-locking shift procedures ........................................................................................194
6.4.5.5 ABR additional parameters............................................................................................................194
6.4.5.6 ABR setup parameters...................................................................................................................195
6.4.5.7 Alternative ATM traffic descriptor.................................................................................................195
6.4.5.8 ATM adaptation layer parameters..................................................................................................195
6.4.5.9 ATM traffic descriptor...................................................................................................................195
6.4.5.10 Broadband bearer capability ........................................................................................................196
6.4.5.11 Broadband high layer information................................................................................................196
6.4.5.12 Broadband low layer information .................................................................................................196
6.4.5.13 Broadband repeat indicator..........................................................................................................1966.4.5.14 Call state .....................................................................................................................................196
6.4.5.15 Called party number....................................................................................................................197
6.4.5.16 Called party subaddress ...............................................................................................................197
6.4.5.17 Calling party number ...................................................................................................................198
6.4.5.18 Calling party subaddress..............................................................................................................198
6.4.5.19 Cause ..........................................................................................................................................198
6.4.5.20 Connected number.......................................................................................................................198
6.4.5.21 Connected subaddress..................................................................................................................198
6.4.5.22 Connection identifier ...................................................................................................................198
6.4.5.23 Connection scope selection ..........................................................................................................198
6.4.5.24 End-to-end transit delay...............................................................................................................198
6.4.5.25 Extended QoS parameters............................................................................................................200
6.4.5.26 Minimum acceptable ATM traffic descriptor................................................................................200
6.4.5.27 Notification indicator...................................................................................................................200
6.4.5.28 Quality of service parameter ........................................................................................................200
6.4.5.29 Restart indicator ..........................................................................................................................200
6.4.5.30 Transit network selection.............................................................................................................200
6.4.5.31 Generic identifier transport..........................................................................................................201
6.4.6 Information elements specific to PNNI..................................................................................2016.4.6.1 Calling party soft PVPC or PVCC..................................................................................................201
6.4.6.2 Called party soft PVPC or PVCC...................................................................................................202
6.4.6.3 Crankback.....................................................................................................................................203
6.4.6.4 Designated transit list....................................................................................................................206
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6.4.7 Information Elements for the support of 64 kbit/s based circuit mode services ......................2086.4.7.1 Narrow-band bearer capability.......................................................................................................208
6.4.7.2 Narrow-band high layer compatibility. ........ ........ ........ .......... ........ ........ ........ ......... ........ ......... ....... 208
6.4.7.3 Narrow-band low layer compatibility.............................................................................................208
6.4.7.4 Progress indicator..........................................................................................................................208
6.4.8 Information Elements for Point-to-Multipoint Call/connection Control.................................2086.4.8.1 Endpoint reference ........................................................................................................................208
6.4.8.2 Endpoint state ...............................................................................................................................208
6.5 CALL/CONNECTION CONTROL PROCEDURES FOR ATM POINT-TO-POINT CALLS ................................208
6.5.1 Establishment of a signalling AAL ................... ...................... ................... ...................... ......209
6.5.2 Call/connection establishment ..............................................................................................2096.5.2.1 Call/connection request .................................................................................................................209
6.5.2.2 Connection identifier allocation/selection.......................................................................................210
6.5.2.2.1 Associated signalling..............................................................................................................210
6.5.2.2.2 Non-associated signalling.......................................................................................................211
6.5.2.2.2.1 Allocation for switched virtual channels ..........................................................................211
6.5.2.2.2.2 Allocation for switched virtual paths................................................................................212
6.5.2.2.3 Use of VPCIs..........................................................................................................................212
6.5.2.2.4 VPCI and VCI ranges .............................................................................................................213
6.5.2.3 Service category, traffic parameter, and QoS selection procedures..................................................213
6.5.2.3.1 Determination of service category...........................................................................................213
6.5.2.3.2 Allowed combination of bearer capabilities, traffic parameters, and QoS ........ ........ ........ ........ 213
6.5.2.3.3 Traffic parameter selection procedures....................................................................................213
6.5.2.3.4 Procedures for negotiation of traffic parameters during call/connection setup ........ ........ ........ ..214
6.5.2.3.5 QoS parameter selection procedures .......................................................................................215
6.5.2.3.6 Traffic parameter selection procedures for ABR connections...................................................217
6.5.2.3.7 Processing of Cumulative RM fixed round-trip time parameter for ABR connections ....... ....... 219
6.5.2.4 Call/connection proceeding............................................................................................................219
6.5.2.5 Call/connection alerting.................................................................................................................220
6.5.2.6 Call/connection connected .............................................................................................................220
6.5.2.6.1 Procedures for traffic parameter selection during call/connection acceptance...........................220
6.5.2.6.2 Procedures for negotiation of traffic parameters during call/connection acceptance... ........ ....... 221
6.5.2.7 Failure of call establishment..........................................................................................................221
6.5.2.8 Generic identifier transport procedures .........................................................................................221
6.5.3 Call/connection clearing.......................................................................................................2216.5.3.1 Terminology..................................................................................................................................222
6.5.3.2 Exception conditions .....................................................................................................................222
6.5.3.3 Clearing ........................................................................................................................................222
6.5.3.4 Clear collision ...............................................................................................................................222
6.5.4 Call/connection collisions.....................................................................................................223
6.5.5 Restart Procedures ...............................................................................................................2236.5.5.1 Sending RESTART .......................................................................................................................223
6.5.5.2 Receipt RESTART ........................................................................................................................223
6.5.5.3 Restart collision.............................................................................................................................223
6.5.6 Handling of error conditions.................................................................................................2236.5.6.1 Protocol discrimination error .........................................................................................................224
6.5.6.2 Message too short..........................................................................................................................224
6.5.6.3 Call reference error........................................................................................................................224
6.5.6.3.1 Invalid call reference format...................................................................................................2246.5.6.3.2 Call reference procedural errors..............................................................................................224
6.5.6.4 Message type or message sequence errors ......................................................................................224
6.5.6.5 Message length error .....................................................................................................................225
6.5.6.6 General information element errors................................................................................................225
6.5.6.6.1 Information element sequence.................................................................................................225
6.5.6.6.2 Duplicated information elements ............................................................................................225
6.5.6.6.3 Coding standard error.............................................................................................................225
6.5.6.7 Mandatory information element error.............................................................................................225
6.5.6.7.1 Mandatory information element missing .................................................................................225
6.5.6.7.2 Mandatory information element content error .........................................................................225
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6.5.6.8 Non-mandatory information element errors ......... ........ ........ ......... ........ ........ ........ .......... ........ ........ 225
6.5.6.8.1 Unrecognized information element .........................................................................................225
6.5.6.8.2 Non-mandatory information element content error ........ ........ ........ .......... ........ ........ ........ ........ 226
6.5.6.8.3 Unexpected recognized information element...........................................................................226
6.5.6.9 Signalling AAL reset.....................................................................................................................226
6.5.6.10 Signalling AAL failure.................................................................................................................226
6.5.6.11 Status enquiry procedure..............................................................................................................227
6.5.6.12 Receiving a STATUS message.....................................................................................................2276.5.7 Error procedures with explicit action indicator.....................................................................227
6.5.7.1 Unexpected or unrecognized message type.....................................................................................227
6.5.7.2 Information element error ..............................................................................................................227
6.5.8 Handling of messages with insufficient information ..............................................................228
6.5.9 Network node call control requirements................................................................................228
6.5.10 Notification procedures ......................................................................................................228
6.5.11 Notification of interworking................................................................................................228
6.5.12 List of Timers......................................................................................................................228
6.6 CALL/CONNECTION CONTROL PROCEDURES FOR POINT-TO-MULTIPOINT CALLS..............................228
6.6.1 Setup of the initial party .......................................................................................................229
6.6.2 Adding a party......................................................................................................................229
6.6.3 Party dropping......................................................................................................................230
6.6.4 Restart procedures................................................................................................................2306.6.5 Handling of error conditions.................................................................................................230
6.6.6 List of timers for point-to-multipoint.....................................................................................230
7. ANNEX A: DESIGNATED TRANSIT LIST ........... ............. ............... ............. ............... ............. .231
7.1 TERMINOLOGY .............................................................................................................................231
7.2 INITIAL DTL PROCESSING .............................................................................................................231
7.2.1 Procedures at the DTL originator ...................... ............................ ............................ ...........231
7.2.2 Procedures at an entry border node......................................................................................232
7.2.3 Procedures at a node which is not the DTL originator or an entry border node ....................233
7.3 NEXT STEP IN DTL PROCESSING ....................................................................................................234
7.4 RECOMMENDATIONS ON INCLUSION OF PORT IDS IN DTLS .............................................................235
7.5 PSEUDOCODE OF DTL PROCEDURES ..............................................................................................235
7.6 EXTERIOR ROUTES AND DTLS.......................................................................................................237
8. ANNEX B: CRANKBACK PROCEDURES..................................................................................238
8.1 SCOPE OF CRANKBACK PROCEDURES .............................................................................................238
8.2 CRANKBACK CAUSE......................................................................................................................238
8.2.1 Reachability Errors ..............................................................................................................2388.2.1.1 Destination unreachable and transit network unreachable ..............................................................239
8.2.1.2 Next node unreachable ..................................................................................................................239
8.2.2 Resource Errors....................................................................................................................2408.2.2.1 Resource Errors Due To Service Category......................................................................................240
8.2.2.2 Resource Errors Due to Traffice and QoS Parameters.....................................................................240
8.2.2.3 Resource Errors Due to VPCI/VCI Allocation ........ ........ ........ ......... ........ ........ ........ .......... ........ ..... 240
8.2.3 DTL Processing Errors ............. ............. ............... ............. ............... ............. ............. ..........241
8.3 PROCEDURES FOR CRANKBACK LEVEL AND BLOCKED TRANSIT.......................................................2418.3.1 Procedures at the Point of Blocking......................................................................................241
8.3.1.1 Blocking at a node.........................................................................................................................241
8.3.1.2 Blocking at the preceding end of a link..........................................................................................241
8.3.1.3 Blocking at the succeeding end of a link ........................................................................................242
8.3.2 Receiving a clearing message with a Crankback information element...................................2428.3.2.1 Receiving a clearing message indicating blocking at this interface..................................................242
8.3.2.2 Receiving a clearing message at the entry border node at the crankback level.................................243
8.3.2.2.1 Alternate routing ....................................................................................................................243
8.3.2.2.2 Crankback to next higher level ...............................................................................................243
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8.3.2.3 Additional procedures for point-to-multipoint calls/connections ........ ........ ........ .......... ........ ........ ...244
8.3.3 Pseudocode of Crankback Procedures .................................... ............................ ........... .......244
8.4 CARRYING UPDATED TOPOLOGY STATE PARAMETERS IN CRANKBACK INFORMATION ELEMENT .......246
9. ANNEX C: SOFT PERMANENT VIRTUAL CONNECTION PROCEDURES....... ............. ......248
9.1 MESSAGES ...................................................................................................................................248
9.2 PROCEDURES FOR POINT-TO-POINT SOFT PVPC/PVCCS .................................................................2489.2.1 Initiating PVPC/PVCC establishment ...................................................................................248
9.2.2 Receiving a CONNECT message at the calling NI ............................... .................................249
9.2.3 Receiving a SETUP message at the called NI........................................................................2499.2.3.1 Last PVPC segment VPI allocation/selection..................................................................................249
9.2.3.2 Last PVCC segment VPI/VCI allocation/selection..........................................................................249
9.3 PROCEDURES FOR POINT-TO-MULTIPOINT PVCCS ..........................................................................250
9.3.1 Adding a party at the originating interface ....................... ............................ ........................250
9.3.2 Set up of the first party .........................................................................................................2509.3.2.1 Receiving a CONNECT message at the calling NI ........ ........ ........ ......... ........ ......... ........ ......... ...... 250
9.3.2.2 Receiving a SETUP message at the called NI.................................................................................250
9.3.3 Adding a party......................................................................................................................2509.3.3.1 Receiving an ADD PARTY ACKNOWLEDGE message at the calling NI ........ ........ ........ ......... ..... 251
9.3.3.2 Receiving an ADD PARTY message at the called NI ........ ........ ........ .......... ........ ........ ........ ......... ..251
9.3.3.2.1 Last PVCC segment VPI/VCI and Endpoint reference allocation/selection. ........ ........ ........ ....251
10. ANNEX D: ARCHITECTURAL CONSTANTS............. ............. ............... ............. ............... .....252
11. ANNEX E: ARCHITECTURAL VARIABLES............ ............. ............... ............. ............... .......253
12. ANNEX F: CONFIGURATION OF THE PNNI HIERARCHY............ ............. ............... .........255
13. ANNEX G: PNNI MINIMUM SUBSETS.....................................................................................257
14. ANNEX H: THE PNNI MANAGEMENT INFORMATION BASE ...Error! Bookmark not defined.
15. APPENDIX A: EXAMPLES OF MESSAGE SEQUENCES.......................................................339
15.1 GENERAL ...................................................................................................................................339
15.2 FINITE STATE MACHINE..............................................................................................................339
15.3 EXAMPLE OF MESSAGE SEQUENCES .............................................................................................339
15.3.1 Successful Call Establishment.............................................................................................339
15.3.2 Unsuccessful Call Establishment.........................................................................................340
15.3.3 Normal call clearing (from originator)................................................................................341
15.3.4 Call termination by a Private network.................................................................................341
16. APPENDIX B: DERIVATION OF GENERIC CONNECTION ADMISSION CONTROL ......342
16.1 GENERIC CAC FOR CBR AND VBR SERVICE CATEGORIES ...........................................................342
16.2 GENERIC CAC FOR UBR AND ABR SERVICE CATEGORIES ...........................................................344
17. APPENDIX C: GUIDELINES FOR TOPOLOGY AGGREGATION........................................345
17.1 DIAMETER AND RADIUS ..............................................................................................................345
17.2 PRESUMED NODAL STATE PARAMETERS ......................................................................................345
17.3 SIGNIFICANT EXCEPTIONS ...........................................................................................................345
17.4USELESS EXCEPTIONS .................................................................................................................345
17.5 NUMBER OF EXCEPTIONS ............................................................................................................345
18. APPENDIX D: MULTI-PEER GROUP SYSTEMS ............ ............. ............... ............. .............. .346
18.1 TECHNICAL DETAILS...................................................................................................................346
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18.1.1 Peer Group Leader .............................................................................................................346
18.1.2 Border Systems ...................................................................................................................346
18.1.3 Core System in a Very Branchy Network.............................................................................348
18.1.4 Backbone and Local Area Topology....................................................................................348
18.2 PROPOSED DISPOSITION OF THIS SECTION ...................................................................................349
19. APPENDIX E: ALLOCATING RESOURCES IN TRANSIT PEER GROUPS............ ............. 350
20. APPENDIX F: PNNI PACKET SIZES.........................................................................................351
20.1 PNNI HELLO PACKET (PHP).......................................................................................................351
20.2 PNNI TOPOLOGY STATE PACKET (PTSP)....................................................................................351
20.3 PTSE ACKNOWLEDGEMENT PACKET (PTSE_AP)........................................................................353
20.4 DATABASE SUMMARY PACKET (DBSP)........................................................................................353
20.5 PTSE REQUEST PACKET (PTSE_RP)...........................................................................................354
21. APPENDIX G. FLOODING PARAMETER SELECTION GUIDELINES................................355
21.1 BASIC PARAMETER RELATIONS....................................................................................................355
21.2 HIGHER HIERARCHICAL LEVELS ..................................................................................................355
21.3 VARYING THE PEERDELAYEDACKINTERVAL................................................................................355
21.4 DEFAULT PEERDELAYEDACKINTERVAL VALUE ...........................................................................355
22. APPENDIX H: A SAMPLE ALGORITHM FOR ROUTE GENERATION............. ............. ....357
23. APPENDIX I: USING PNNI TO CONNECT NON-PNNI ROUTING DOMAINS.......... ..........365
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List of Figures
Figure 1-1: Switching System Architectural Reference Model ........................................ ...........................1
Figure 3-1: Private ATM network with 26 switching systems and 33 bi-directional links. ............ ............13
Figure 3-2: Partially configured PNNI hierarchy showing lowest level nodes. ........................................14
Figure 3-3: Partially configured PNNI hierarchy showing lowest hierarchical levels..............................19Figure 3-4: Uplinks.................................................................................................................................22
Figure 3-5: Complex node representation of LGN A.4 from Figure 3-3...................................................25
Figure 3-6: Example of a complete PNNI hierarchically configured network. .........................................26
Figure 3-7: Uplinks revisited. .................................................................................................................28
Figure 3-8: Address summarization in a PNNI hierarchy. ............. ............. ............... ............ ............... ...30
Figure 3-9: Sample Network ...................................................................................................................33
Figure 3-10: View of the network from nodes A.3.3, A.3.2, A.3.1, and A.3.4............................................35
Figure 4-1: ATM Interfaces.....................................................................................................................39
Figure 4-2: A Sample Hierarchical Network ...................... ............................ ............................ .............41
Figure 4-3: An Example of Crankback and Alternate Routing.................................................................42
Figure 5-1: NSAP Address Structure and Address Prefixes .....................................................................48
Figure 5-2: Peer Group Identifier 14 octet encoding...............................................................................50
Figure 5-3: An SVCC-Based RCC and horizontal links between a Lowest-Level Node and an LGN.........59Figure 5-4: Hello State Changes.............................................................................................................65
Figure 5-5: LGN Horizontal Link Hello FSM..........................................................................................80
Figure 5-6: Neighboring Peer State Changes (Database Synchronization)............ ............. ............... ......88
Figure 5-7: PGL Election FSM. ................... ...................... ................... ..................... ................. ..........121
Figure 5-8: Peer Group with Five Border Nodes...................................................................................135
Figure 5-9: Default Node Representation..............................................................................................136
Figure 5-10: Complex Node Representation with Exceptions ............................................................... .136
Figure 6-1 PNNI interface ............. ............ ............... ............. ............... ............. ............. ............... ......173
Figure 6-2 PNNI Control Plane ............. ............. ............... ............. ............... ........